Wiper arrangement

ABSTRACT

A wiper system has a wiper motor and a gear secured via a receptacle to a tubular carrier by fastening regions formed onto its gear box, and the receptacle surrounds the tubular carrier in form- and/or force-locking fashion.

BACKGROUND OF THE INVENTION

The invention is based on a wiper system as.

Wiper systems, especially for motor vehicles, are secured to the motorvehicle body and substantially comprise a wiper drive, which via a driveshaft and rod linkage drives power takeoff shafts, which are supportedin wiper bearings that protrude from the vehicle body and onto whichwipers are placed.

The wiper drive comprises a wiper motor and a gear, whose gearbox has abearing support, in which an outward-protruding drive shaft is guided.The wiper drive must be fixed in the axial and circumferentialdirections so that the reaction forces of the torque to be transmittedand the forces of gravity can be absorbed. From European PatentDisclosure EP 409 944 B1, a wiper system is known that is secured by areceptacle for the wiper drive to the body of the motor vehicle. Thewiper drive is connected to the receptacle via three threaded joint legsdisposed in a triangle about the bearing support, or else is integrallyformed onto the gearbox. The receptacle is adjoined at the side bytubular carriers for the wiper bearings. They are slipped ontoprojections and form-lockingly joined to them, preferably by beingsnapped into recesses. The snap placement creates an inseparableconnection. In wiper systems with two wiper bearings, two tubularcarriers are also needed, which are joined to the receptacle or thegearbox via two interfaces.

A wiper system with a tubular carrier on which two wiper bearings can besecured is also known from the prior art. The receptacle for the wiperdrive is welded to the tubular carrier. The wiper drive is secured inturn to the receptacle with three threaded joint legs disposed in atriangle about the bearing support.

SUMMARY OF THE INVENTION

The embodiment according to the invention as has the advantage that twowiper bearings can be disposed on one tubular carrier, so that thereceptacle is connected form- and/or force-lockingly to the tubularcarrier by only one interface. The result is attained is lightweight,compact connections which in most versions are at the same timeseparable again, and which can be monitored economically and easily. Thematerials are joined together without the addition of heat, so that anyhardening, changes in the microstructure, or embrittlement that might becaused thereby are precluded. Materials of different kinds can be easilyjoined to one another. The parts can be mounted using simple tools.

In addition, reject parts are reduced, because the connection can beundone again to correct assembly errors or for replacement of defectiveparts. One receptacle can be used for different tubular carriers, andthe wiper system can be adapted to different built-in variations, inthat the receptacle is slipped onto the tubular carrier and/or rotatedabout angular ranges that are specified by the form-locking contour.

In the automotive industry, economizing a weight with the attendant fuelsavings are especially important today. Even slight economies in manysmall individual components are important, because they reduce the totalweight considerably directly as well as indirectly by smallerdimensioning of the adjoining components. According to the invention,the tubular carrier is made by an internal high-pressure process (IHV),and as a result it can be made hollow, stiff, relatively thin-walled,and thus especially light in weight.

In principle, both a purely form-locking and a purely force-lockingconnection are conceivable. Preferably, however, the two types ofconnection are used in combination, so that on the one hand strongforces and moments can be absorbed by the form lock and on the otherfreedom in terms of play can be attained because of the force lock.According to the invention, the form lock is attained in thecircumferential direction with a nonround form of the tubular carrierand a suitable outer contour of the receptacle, such as a contour otherthan the circular, such as polygonal or in some other way, regular orirregular, elliptical, or with sets of teeth. In the longitudinaldirection, a force-locking connection often suffices. If major forcesmust be absorbed in the longitudinal direction as well, however, then aform lock can additionally be attained by means of a contour, dimensionor orientation of the tubular carrier that varies in the longitudinaldirection.

A further contribution to a compact, lightweight mode of construction ismade by a receptacle that is formed entirely or in part onto thegearbox. Interfaces, individual parts, and thus assembly effort andexpense as well as weight can thus be reduced.

Simple assembly is especially important in large-scale production.Simple assembly is attained according to the invention with a tubularcarrier that is placed in an indentation in the receptacle inform-locking fashion in the longitudinal direction and/or thecircumferential direction and then fixed force-lockingly with a clipthat closes the indentation. In special cases, for instance under heavyload, an additional form-locking connection between the clip and thetubular carrier may be appropriate.

If an indentation is formed in part or entirely by one or more fasteningregions of the gearbox that are embodied as threaded joint legs, and ifthe screw thereof is used for the force lock with the clip, thenexisting components are assigned additional functions, while additionalcomponents are avoided, thus saving weight and space. A furthercontribution in this respect is made by a clip screwed onto only oneside which on the other side is suspended form-lockingly from thegearbox or the receptacle. A clip of this kind can be installed andremoved quickly.

The number of interfaces can also be reduced by means of receptaclesformed entirely on the gearbox. In a feature of the invention, this isattained with receiving faces that are formed onto the feet of what arepreferably two threaded joint legs. The tubular carrier is fixedforce-lockingly, and possibly form-lockingly as well, in the receivingfaces. To this end, it has openings or stepped bores through which thethreaded joint legs are inserted. The force lock is created with thescrews of the threaded joint legs with which the tubular carrier ispressed into the receiving faces. The result is a very compact,lightweight construction with only a few components. To distribute theclamping force uniformly over the tubular carrier and to attain goodguidance, a reinforcing shell may be placed between the screws and thetubular carrier. In particular, the clamping force can be betterdistributed and advantageous centering can be attained without anyadditional element, by forming conical supports onto the tubularcarrier, preferably by means of an internal high-pressure process, thesupports then form-lockingly adjoining suitably shaped threaded jointlegs. Formed-on supports can also be utilized to center the tubularcarrier in the receiving faces. Better guidance and force distributioncan also be attained with a larger pitch circle of the threaded jointlegs, because then the spacing between the force introduction points isincreases.

It is often advantageous for work operations to be integrated intoexisting method steps in manufacture. This allows a considerablereduction in the effort and expense of assembly and in the number ofinterfaces. According to the invention, this is achieved with aninternal high-pressure process. To that end, a stamped/bent componentwhich has shells placed high and low is preferably used as thereceptacle. A still round tubular carrier is thrust through the shellsand then placed in an internal high-pressure-process tool with thereceptacle. The tubular carrier is then acted upon by pressure, whichcauses it to pressure together with the shells against the inner wall ofthe internal high-pressure-process tool. The inner wall is preferablynonround, so that a form lock is attained in the circumferentialdirection between the receptacle and the tubular carrier. The shells canbe preshaped in nonround fashion from the outset, to suit the innercontour of the internal high-pressure-process tool. Preferably, they arepreshaped enough that by means of a joint deforming operation a durableform- and force-locking connection is created between the tubularcarrier and the shells, without having to employ excessive forces,because of the accumulation of material.

BRIEF DESCRIPTION OF THE DRAWING

In the drawing, exemplary embodiments of the invention are shown. Thedescription and the claims contain numerous characteristics inconjunction with one another. One skilled in the art will expedientlyalso consider the characteristics individually and make furtherappropriate combinations of them.

Shown are:

FIG. 1, a view from above of a wiper system with a receptacle;

FIG. 2, a sectional view taken along the line II—II of FIG. 1;

FIG. 3, a view of a wiper drive with a partly formed-on receptacle;

FIG. 4, a sectional view taken along the line IV—IV of FIG. 3;

FIG. 5, a wiper system with the receptacle formed on completely;

FIG. 6, a sectional view through the tubular carrier taken along theline VI—VI of FIG. 5;

FIG. 7, a view plan view of FIG. 6;

FIG. 8, a view of a wiper system with a bed board with shelves placehigh and low;

FIG. 9, a sectional view taken along the line IX—IX of FIG. 8; and

FIG. 10, the tubular carrier and the receptacle of FIG. 8, in aninternal high-pressure-process tool.

DESCRIPTION OF THE PREFFERED EMBODIMENTS

In FIGS. 1 and 2, a wiper system is shown, with a wiper motor 10 andwith a gear 12 whose gearbox 14 has a bearing support 46, in which anoutward-protruding drive shaft 48 is guided, around which threefastening regions 16, 34, 36, embodied as threaded joint legs 16, 34,36, are arranged in a triangle, offset from one another by 120° each.The gearbox 14 is connected to a tubular carrier 20 (FIG. 2) via areceptacle 18 comprising two clips 64, 26. Preferably, two threadedjoint legs 34, 36 are disposed side by side in the direction 58 of thetubular carrier 20 and parallel to the tubular carrier. The first clip64 in the receptacle 18 is placed onto the threaded joint legs 16, 34,36. It is screwed with a screw 32 to one threaded joint leg 16, which ispreferably the one farthest away from the tubular carrier 20 as comparedto the other threaded joint legs 34, 36. The tubular carrier 20 is thenform-lockingly placed in the circumferential direction and/or thelongitudinal direction 22 in a channel-shaped indentation. This can beachieved for instance with sets of teeth or other kinds of non-roundprofiling. Especially in the longitudinal direction 22, a form lock bymeans of a contour, dimension or orientation of tubular carrier 20 thatvaries in this direction is conceivable, for instance in that thetubular carrier is deformed crosswise to the longitudinal direction 22where it adjoins the clips 26, 64.

The indentation 24 is then closed with the second clip 26, in that thisclip is suspended in form-locking fashion, on the side 28 pointing awayfrom the gear 12, in the first clip 64, as shown for instance in FIG. 2,in an opening 72 extending in the longitudinal direction 22. On theopposite 30 of the tubular carrier 20, the clip 26 is screwed to twothreaded joint legs 34, 36 disposed parallel to the tubular carrier 20.The clip 26 is braced against the tubular carrier 20, possibly even inform-locking fashion, and as a result when the clip 26 is screwed on aclamping force on the tubular carrier 20 is created. The tubular carrieris thus fixed in form- and force-locking fashion in the indentation 24.The clips 26, 64 extend at least across the spacing between the twothreaded joint legs 34, 36 located in the direction 58, and as a result,given a distributed clamping force, good guidance is attained withoutcritical pressure per unit of surface area.

The threaded joint legs 16, 34, 36, including their screws 32,advantageously end in the same plane in the direction 54 of the driveshaft 48, so that a rod linkage to be secured to the drive shaft 48 canmove freely without having to be adapted to threaded joint legs 16, 34,36 protruding any farther outward. This is attained for instance with aclip 64 (FIG. 2) that in the direction 58 has a shoulder 56 extending inthe region 70 toward the gearbox 14 and that rests on bearing faces 52,offset in the direction 70, on the threaded joint legs 34, 36 disposedside by side and parallel to the tubular carrier 20. The height of theshoulder is approximately equivalent to the thickness of the second clip26, so that the upper edges of the screws 32 are located virtually inthe same plane. The flow of force between the two clips 26, 64 becomesfavorable when these clips are pressed against one another. This isattained for instance with threaded joint legs 34, 36 in which thespacing between the bearing face 52 and the end face 74 is less than thethickness of the first clip 64, and thus the clips 26, 64 come intomutual contact as a result of the screwing operation.

In FIGS. 3 and 4, a wiper system with a receptacle 38 partly formed ontothe gearbox 14 is shown. The gearbox 14 has three threaded joint legs16, 34, 36, which again are arranged in a triangle around the driveshaft 48. The first clip 64 is replaced by an indentation 78 formed ontothe gearbox 14. A wall 60 of the indentation 78 is formed by twothreaded joint legs 34, 36, which can be shaped suitably for thispurpose. The tubular carrier 20 and the indentation 78 havecomplementary outer contours, so that the tubular carrier 20 can beplaced formed-lockingly into the indentation 78. The tubular carrier 20preferably has a rounded outer contour and is flattened in the directionof the threaded joint legs 34, 36, so that it comes into contact withthem in form-locking fashion. Form-locking connections as in theexemplary embodiment of FIGS. 1 and 2 are also conceivable.

By means of a clip 26, the tubular carrier 20 is pressed force-lockinglyinto the indentation 78. The clip is suspended on one side 28, extendingin the direction 58 from the tubular carrier 20, from a protrusion 62 inthe gearbox 14, so that the clip can absorb the reaction forces of theclamping force. On the opposite side 30, the clip 26 is screwed to thegearbox 14 by the screws 32, as a result of which the clamping force isintroduced. The clip 26 extends over virtually the entire width of thegear 12, and as a result good guidance with distributed pressure perunit of surface area is attained.

In FIGS. 5-7, a feature of the invention with a receptacle 40 formedcompletely onto the gearbox 14 is shown. Receiving faces 44 (see FIG. 6)are formed onto feet 80 of the threaded joint legs 34, 36, which aredisposed parallel to the carrier 20 and have a contour corresponding tothe outer contour of the tubular carrier 20. The tubular carrier 20 hastwo stepped bores 66, so that it can be placed in the receiving faces 44with the threaded joint legs 34, 36 reaching through it. Next, thetubular carrier 20 is fixed in force-locking fashion in the receivingfaces 44 by means of the screws 32. Preferably, the receiving faces 44and the tubular carrier 20 are joined together in form-locking fashion,in addition to the force lock. This can be attained once again in boththe longitudinal direction 22 and their circumferential directionanalogously to the connections described above. With a reinforcing shell82 disposed between the screws 32 and the tubular carrier 20, theclamping force is distributed over a larger area on the tubular carrier20. This prevents critical pressures per unit of surface area.

In FIGS. 8-10, a variant of a wiper system is shown, with a receptacle42 reshaped jointly with the tubular carrier 20. The receptacle 42comprises a one-piece bed board with shells 84, 90 protruding inalternation to one side or the other and made by a stamping and bendingoperation. The receptacle 42 is thrust with the shells 84, 90 onto thetubular carrier 20. Next, the two workpieces 42, 20 are placed in areshaping tool, preferably an internal high-pressure-process tool 86(FIG. 10). With the internal high-pressure process, various productionsteps can be combined, such as the forming on of wiper systemreceptacles 68, fastening elements on the body, and so forth.

Once the workpieces 42, 20 have been placed in the internalhigh-pressure-process tool 86, the tubular carrier 20 is acted upon bypressure, causing it and the shells 84, 90 to press against the innerwall 88 of the internal high-pressure-process tool 86, for example as aresult of increasing the internal pressure via a pressure medium supplyline 76. The inner wall 88 is preferably non round, so that a form lockcan be created in the circumferential direction between the bed boardand the tubular carrier 20. It is advantageous if the shells 84, 90 arepreshaped in nonround fashion from the onset, to suit the inner wall 88.Preferably, they are preshaped to such an extent that a good form- andforce-locking connection is created between them and the tubular carrier20 by means of internal tensions, and at the same time there is no needto employ excessive forces because of material accumulation.

What is claimed is:
 1. A wiper system, comprising a wiper motor (10) anda gear (12) that is secured via a receptacle (18, 38, 40, 42) to atubular carrier (20) by fastening regions (16, 34, 36) formed onto agearbox (14), the receptacle (18, 38, 40, 42) surrounding the tubularcarrier (20) in a fashion selected from the group consisting ofform-locking fashion, force-locking fashion and both, the tubularcarrier (20) being placed form-lockingly in a direction selected fromthe group consisting of a longitudinal direction, a circumferentialdirection, and both into an indentation (24, 78) of the receptacle (18,38), and a fastening region (34, 36) forming a part of the indentation(78).
 2. The wiper system of claim 1, characterized in that the tubularcarrier (20) is produced by an internal high-pressure process (IHV). 3.The wiper system of claim 1, with the tubular carrier (20) has anonround form in the circumferential direction and/or a varying contour,dimension or orientation in the longitudinal direction (22).
 4. Thewiper system of claim 1, wherein the receptacle (18, 38, 40) is formedentirely or in part onto the gearbox (14).
 5. The wiper system of claim1, that a clip (26) that closes the indentation (24, 78) fixes thetubular carrier (20) in force-locking fashion.
 6. The wiper system ofclaim 5, wherein the clip (26) fixes the tubular carrier (20) inform-locking fashion in the circumferential and/or the longitudinaldirection (22).
 7. A method for producing a connection selected from thegroup consisting of a form-locking connection, a force-lockingconnection, and both between a receptacle (42) and a tubular carrier(20), characterized in thrusting a still-round tubular carrier (20) intocorresponding shells (84, 90) in a longitudinal direction (22); placingthe receptacle (42) and the tubular carrier (20) in an internalhigh-pressure-process toll (86); and pressing the tubular carrier (20)jointly with the shells (84, 90) against an inner wall (88) of aninternal high-pressure-process toll (86).
 8. A wiper system, comprisinga wiper motor (10) and a gear (12) that is secured via a receptacle (18,38, 40, 42) to a tubular carrier (20) by fastening regions (16, 34, 36)formed onto a gearbox (14), the receptacle (18, 38, 40, 42) surroundingthe tubular carrier (20) in a fashion selected from the group consistingof form-locking fashion, force-locking fashion and both, the receptacle(18, 38, 40) being formed entirely or in part onto the gear box (14), atleast on a foot (80) of a fastening region (34, 36), a receiving face(44) being formed on that corresponds to the outer contour of thetubular carrier (20); the fastening region (34, 36) reaching through thetubular carrier (20), and the tubular carrier being fixed force-lockingon the gearbox (14) with a screw (32).
 9. The wiper system of claim 8,wherein a reinforcing shell (82) is located between the screw (32) andthe tubular carrier (20).
 10. A wiper system, comprising a wiper motor(10) and a gear (12) that is secured via a receptacle (18, 38, 40, 42)to a tubular carrier (20) by fastening regions (16, 34, 36) formed ontoa gearbox (14), the receptacle (18, 38, 40, 42) surrounding the tubularcarrier (20) in a fashion selected from the group consisting ofform-locking fashion, force-locking fashion and both, the tubularcarrier (20) is placed form-lockingly in a direction selected from thegroup consisting of a longitudinal direction, a circumferentialdirection, and both into an indentation (24, 78) of the receptacle (18,38), a clip (26) that closes the indentation (24, 78) fixes the tubularcarrier (20) in force-locking fashion, the clip (26), on one side (28)of the tubular carrier (20) is suspended form-lockingly in thereceptacle (18, 38) and is braced against the tubular carrier (20), andon the other side (20) is stayed with at least one screw (32).